“FORX is a purer way to gain foreign currency exposure and also avoids the unwanted exposures that can come with holding indirect currency plays such as equities or commodities.”

Many commentators have been warning about the ravages of a dollar decline since the Federal Reserve began easing in 2007.

Indeed, the Trade-Weighted U.S. Dollar Index has dropped 10.4 percent since January 2007. But it is up about 5 percent from mid-2008, shortly before the financial crisis broke out in earnest.

Thus, it’s very difficult to say that the dollar is in an extended downdraft.

The greenback hit a 2 ½-year high against the yen earlier this month, but the euro reached a 14-month peak against the dollar in January. So it’s a mixed bag.

The Pimco ETF commenced trading Tuesday with a 15 percent exposure to both the Norwegian krone and Canadian dollar, a 9.5 percent exposure to the Russian ruble, a 9.2 percent exposure to the Mexican peso and an 8 percent exposure to the Swedish krona, according to the Financial Times.

The issue of currency valuation has jumped to the fore, as easing by central banks has raised concern about a potential currency war.

Such a war already has begun in the eyes of James Rickards, senior managing director of Tangent Capital Partners.

It started in 2010 on the heels of the Federal Reserve’s massive easing program, he tells Wall Street Journal Digital Network. Since then, plenty of nations have joined in, including Brazil, Switzerland and Japan, Rickards says.

“All major central banks are easing,” he says. “Eventually so much money will be printed that this will lead to inflation. The endgame is collapse of the international monetary system — sometime sooner than later.”